There is one exception to the "just say no to the back room" advice given here. If they claim to have received information that you have been involved in "gross or serious sin" then if you refuse to meet with them, they can DF you in absentia. But chances are they would at least tip their hand a little bit if they were pulling you in for something judicial. Just to make sure, you could say something like, "No, I'm fine right now. Thanks. No one's accusing me of "gross sin" or anything are they?"
If you ask them straight up, they'll have to admit one way or the other if they're trying to hang you with a Judicial Committee. Short of "gross sins", you can politely decline and you're pretty much untouchable. But don't cop TOO much of an attitude or they could play the "Loose Conduct" card on you. (Blatant and shocking disrespect for Theocratic Order or words to that effect.)
Best of luck with your education, career and fade!